Header

UZH-Logo

Maintenance Infos

Carbenoid reactions of Dimethyl Diazomalonate with aromatic Thioketones and 1,3-Thiazole-5(4H)-thiones


Mloston, Grzegorz; Heimgartner, Heinz (1996). Carbenoid reactions of Dimethyl Diazomalonate with aromatic Thioketones and 1,3-Thiazole-5(4H)-thiones. Helvetica Chimica Acta, 79(7):1785-1792.

Abstract

Dimethyl diazomalonate (4) and thiobenzophenone (2a) do not react in toluene even after warming to 50°. After addition of catalytic amounts of Rh2(OAc)4, a smooth reaction under N2 evolution afforded a mixture of thiiranedicarboxylate 5 and (diphenylmethylidene)malonate 6 (Scheme 2 ). A reaction mechanism via an intermediate ‘thiocarbonylylide’ 7, formed by the addition of the carbenoid species 8 to the S-atom of 2a, is plausible. Similar reactions were carried out with 9H-xanthene-9-thione (2b), 9H-thioxanthene-9-thione (2c, Scheme 4 ), and 1,3-thiazole-5(4H)-thione 18 (Scheme 6). In the cases of 2b and 2c, spirocyclic 1,3-dithiolanetetracarboxylates 14a and 14b, respectively, were obtained as the third product. Reaction mechanisms for their formation are proposed in Scheme 5: S-transfer from intermediate thiirane 12 to the carbenoid species yielded thioxomalonate 15 which underwent a 1,3-dipolar cycloaddition with ‘thiocarbonyl ylide’ 16. An alternative is the formation of ‘thiocarbonyl ylide’ 17 via carbene addition to 15, followed by 1,3dipolar cycloaddition with 2b and 2c, respectively.

Abstract

Dimethyl diazomalonate (4) and thiobenzophenone (2a) do not react in toluene even after warming to 50°. After addition of catalytic amounts of Rh2(OAc)4, a smooth reaction under N2 evolution afforded a mixture of thiiranedicarboxylate 5 and (diphenylmethylidene)malonate 6 (Scheme 2 ). A reaction mechanism via an intermediate ‘thiocarbonylylide’ 7, formed by the addition of the carbenoid species 8 to the S-atom of 2a, is plausible. Similar reactions were carried out with 9H-xanthene-9-thione (2b), 9H-thioxanthene-9-thione (2c, Scheme 4 ), and 1,3-thiazole-5(4H)-thione 18 (Scheme 6). In the cases of 2b and 2c, spirocyclic 1,3-dithiolanetetracarboxylates 14a and 14b, respectively, were obtained as the third product. Reaction mechanisms for their formation are proposed in Scheme 5: S-transfer from intermediate thiirane 12 to the carbenoid species yielded thioxomalonate 15 which underwent a 1,3-dipolar cycloaddition with ‘thiocarbonyl ylide’ 16. An alternative is the formation of ‘thiocarbonyl ylide’ 17 via carbene addition to 15, followed by 1,3dipolar cycloaddition with 2b and 2c, respectively.

Statistics

Citations

Dimensions.ai Metrics
23 citations in Web of Science®
28 citations in Scopus®
19 citations in Microsoft Academic
Google Scholar™

Altmetrics

Downloads

1 download since deposited on 25 Nov 2013
0 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
Dewey Decimal Classification:540 Chemistry
Language:English
Date:1996
Deposited On:25 Nov 2013 08:15
Last Modified:18 Apr 2018 11:44
Publisher:Wiley-Blackwell
ISSN:0018-019X
Funders:Polish State Committee for Scientific Research (Grant No. 3 TO9A 157 10), Swiss National Science Foundation, F. Hoffmann-La Roche AG, Basel, Swiss Federal Commission for Foreign Students (scholarship)
OA Status:Closed
Publisher DOI:https://doi.org/10.1002/hlca.19960790704
Project Information:
  • : Funder
  • : Grant ID
  • : Project TitlePolish State Committee for Scientific Research (Grant No. 3 TO9A 157 10)
  • : FunderSNSF
  • : Grant ID
  • : Project TitleSwiss National Science Foundation
  • : Funder
  • : Grant ID
  • : Project TitleF. Hoffmann-La Roche AG, Basel
  • : Funder
  • : Grant ID
  • : Project TitleSwiss Federal Commission for Foreign Students (scholarship)

Download